Semiconductor solid-state illumination is one of the most promising new technologies in the twenty-first century, and is essentially based on a high power LED. With progress in semiconductor material growing technologies and component packaging in recent years, luminous efficiency and reliability of the high power LED components have been greatly improved. The LEDs have been increasingly widely applied, especially in illumination applications and display panels, and a packaged LED device having a larger light-emitting angle is more valuable for either the illumination applications or as a backlight source of a display panel.
In the related art, the light-emitting angle of a power-type LED is generally determined by a cup depth of a support, a lens or a reverse mold die. FIG. 1A and FIG. 1B are a front view and a right view of an LED light source in the related art, respectively.
Referring to FIG. 1A and FIG. 1B, the LED light source in the related art includes a housing 11, an LED wafer (not shown in FIG. 1A and FIG. 1B) disposed within the housing 11 and pins 12. Referring to FIG. 1A, a light-emitting angle a of the LED light source is determined by a cavity of a support thereof. For example, as for an LED light source commonly used in a liquid crystal display module of a mobile phone, the light-emitting angle a of the LED light source depends on the cup depth of the support, the lens or the reverse mold die of the LED light source, and the maximum light-emitting angle a of the LED light source is designed as 120°. The LED light source applied in a side light-emitting backlight module is a spot light source and emits light at a sector shape, and thus an undesirable optical phenomenon of “firefly” (i.e. nonuniform light mixing) is very likely caused when the light-emitting angle is small, thus degrading a display effect. In addition, when the LED light source is applied in a backlight source of a display component of a direct type backlight module, the number of the LED light sources in the backlight module needs to be increased if the light-emitting angle of the LED light sources is small, thus increasing product costs.
Referring to FIG. 1B, the LED light source is a linear light source, thus a light guide plate 13 is required to convert the LED light source adopted as the backlight source into an area light source. However, when the LED light source is disposed at a lateral side of the light guide plate 13, an area illuminated by light of the LED light source, areas A, B, and C, is much larger than the lateral side of the light guide plate 13 because a thickness d of the light guide plate 13 is small and a light-emitting angle β of the LED light source in the thickness direction of the light guide plate 13 is too big, so that the light of the LED light source beyond the thickness of the lateral side of the light guide plate 13, i.e. the light in areas A and C shown in FIG. 1B, is wasted, resulting in low utilization efficiency of the light. That is, the related art is defective in that the light-emitting angle of the LED light source cannot be effectively adjusted.